1. Field of the Invention
Exemplary embodiments of the present invention relate to a content caching device, and more particularly, to such a content caching device in which the priority of a content requested by a user terminal is calculated based on content usage features such as the number of requests or the latest request interval of the requested content, and the like, the requested content is controlled to be selectively stored in a short-term storage unit based on the calculated priority of the requested content, and among the contents stored in the short-term storage unit, a content needed to be stored for a long time period is controlled to be stored in a separate long-term storage unit based on the storage time of the requested content in the short-term storage unit.
2. Description of Related Art
Nowadays, the Internet is widely used, and the Internet users download and use a variety of kinds of contents scattered all over the world through the Internet. In other words, in order for an Internet user to have access to a specific content server and use a content provided by the associated content server, it is required that the content server should transmit a packet data corresponding to the content requested by a user terminal through several routers on the way to the user terminal.
In the case where a plurality of Internet users connects to the same content server and uses the same content, the packet data corresponding to the same content is repeatedly transmitted and received between the same content server and the plurality of Inter users through the Internet. This lead to a problem of increasing a degree of traffic congestion.
In order to address and solve the degree of traffic congestion, a system for storing, providing, and managing contents is proposed, which is named a “content caching system”. The content caching system refers to a content storing and providing system in which a content caching device having contents stored therein and connecting to a user terminal is located in a network, and when there is a request for a specific content from a user terminal, the content caching device directly provides a corresponding content stored therein to the user terminal instead of downloading the corresponding content from a content server and providing it to the user terminal, so that the degree of traffic congestion is prevented from being increased and the content desired by the user can be promptly provided to the user terminal.
The content caching device of the above-mentioned conventional content caching system provides the requested content stored in a storage unit to the user terminal, or downloads the requested content from the content server and provides it to the user terminal if the requested content is not stored in the storage unit. The downloaded content is stored in the storage unit, and if there is a request for the same content as the downloaded content from the user terminal or an neighboring user terminal later, the content caching device directly provides the requested content stored in the storage unit to the user terminal or the neighboring user terminal without downloading the requested content from the content server.
However, the conventional content caching device entails a problem in that it stores all the contents requested by the user terminal in the storage unit without taking into consideration the content usage features of the user terminal, so that the storage unit is not used efficiently. That is, such a conventional content caching device stores all the contents in a limited storage space without considering the content usage features, so that the storage efficiency of the storage unit is reduced and the content caching device re-downloads a content deleted due to the excess of the storage capacity from the storage unit, thereby increasing the degree of traffic congestion.